Dr. Robotnik has concocted a diabolical scheme, and it's up to you to stop him. Play as Sonic, Tails, Knuckles or Amy as you collect Chaos Emeralds and thwart his nefarious machines. Sega just sended over 21 screenshots, a bit of art and a logo from the upcoming GBA title Sonic Advance. Release date: 8/3/2002.